Proximity payment cards are in widespread use. A well known standard for such cards has been promulgated by MasterCard International Incorporated, the assignee hereof, and is referred to as “PayPass”. Proximity payment cards typically include a radio frequency identification (RFID) integrated circuit (IC) embedded in a card-shaped plastic body. An antenna is also embedded in the card body. The antenna allows the card to receive a power signal from a point of sale terminal. The antenna is also used by the RFID IC to transmit the payment card account number, and possibly other information as well, to the POS terminal.
It has been proposed to provide an RFID IC card that is installable in a wristwatch or other device so that such device may function as a proximity payment device.